This invention is directed to a device for determining the amount of Vitamin D generated by a person and a current Vitamin D level for that person, and more particularly, a portable device for determining in real time actual generation of Vitamin D for that person as a function of user physical characteristics and sun exposure.
Maintaining proper Vitamin D levels is absolutely critical to each and every person's health. Vitamin D is required for strong bones as it helps the body use calcium found in the diet. Vitamin D deficiencies have been associated with increased risk of death from cardiovascular disease, cognitive impairment in older adults, severe asthma in children, cancer, and rickets. Conversely healthy amounts of Vitamin D may act as a prevention and treatment of conditions including diabetes, hypertension, glucose intolerance and multiple sclerosis.
In a normal state, the body is always deficient in Vitamin D. Therefore, humans must get Vitamin D from other sources, such as certain fruits and vegetables. However, the body also manufactures Vitamin D when skin is exposed to sunlight. Therefore, Vitamin D deficiency often occurs where a person does not get sufficient exposure to sunlight.
Determining the current amount of Vitamin D in the system of a user, short of continuous blood testing, has for centuries, been hit or miss guesswork as a function of “knowing your own body.” The factors going into determining the amount of Vitamin D manufactured by the body is complex, and at a minimum, are a function of body type characteristics, the time of sun exposure, and the intensity of the sun. However, all of these factors are difficult to determine and subject to self-reporting errors as reporting the intensity of the sun, and even some body type characteristics can be a subjective process.
Furthermore, because sun intensity changes with latitude and the seasons, the body manufactures different amounts of Vitamin D from season to season. Additionally, a person in the tropics manufacturers much more Vitamin D, all things being equal, than someone in New York or London. Therefore, it is difficult for a user to adopt a strategy which contains an appropriate level Vitamin D year round.
There are web based tools for approximating daily Vitamin D manufacture that require a user to input all the information such as exposure time of day, exposure duration, location of the sun, and other factors such as skin darkness, height, weight and amount of skin exposed to the sun. The web based calculators then calculate a predicted personal Vitamin D manufacturing amount for that session. These prior art devices have been satisfactory, however they suffer from the disadvantage that they are prone to self-reporting error. Often these determinations are made at a home based computer long after exposure has occurred and inaccurate inputs are provided as a result of faulty memory. Additionally, these calculators only operate on a daily basis and the user must then manually determine overall Vitamin D exposure over a series of sessions and whether they are achieving desired levels across several sessions.
Accordingly, a system and method for determining the amount of Vitamin D manufactured by a person which overcomes the shortcomings of the prior art is desired.